Signatures of pairing in the magnetic excitation spectrum of strongly correlated two-leg ladders

Magnetic interactions are widely believed to play a crucial role in the microscopic mechanism leading to high critical temperature superconductivity. It is therefore important to study the signatures of pairing in the magnetic excitation spectrum of simple models known to show unconventional superco...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. B 2017-11, Vol.96 (20), Article 205120
Main Authors: Nocera, A., Patel, N. D., Dagotto, E., Alvarez, G.
Format: Article
Language:English
Subjects:
CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
Correlation
Doping
Excitation spectra
Inelastic scattering
Ladders
Magnetic materials
Magnetic properties
Neutron scattering
Signatures
Spin dynamics
Spin structure
Structure factor
Superconductivity
Weight
X-ray scattering
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Magnetic interactions are widely believed to play a crucial role in the microscopic mechanism leading to high critical temperature superconductivity. It is therefore important to study the signatures of pairing in the magnetic excitation spectrum of simple models known to show unconventional superconducting tendencies. Using the density matrix renormalization group technique, we calculate the dynamical spin structure factor S(k,ω) of a generalized t−U−J Hubbard model away from half filling in a two-leg ladder geometry. The addition of J enhances pairing tendencies. We analyze quantitatively the signatures of pairing in the magnetic excitation spectra. We found that the superconducting pair-correlation strength, that can be estimated independently from ground state properties, is closely correlated with the integrated low-energy magnetic spectral weight in the vicinity of (π,π). In this wave-vector region, robust spin incommensurate features develop with increasing doping. The branch of the spectrum with rung direction wave vector krung=0 does not change substantially with doping where pairing dominates and thus plays a minor role. We discuss the implications of our results for neutron scattering experiments, where the spin excitation dynamics of hole-doped quasi-one-dimensional magnetic materials can be measured and also address implications for recent resonant inelastic x-ray scattering experiments.
ISSN:2469-9950
2469-9969
DOI:10.1103/PhysRevB.96.205120